Plastic pallet

ABSTRACT

A nestable plastic pallet that can be stacked to have a reduced stack height. The pallet includes a single wall of homogeneous material that defines a substantially flat load-supporting surface. The load-supporting surface has perimeter edges, and the pallet has an underside opposite the load-supporting surface. Perimeter edges of the pallet have raised lips, which project from the load-supporting surface. The perimeter edges also have downwardly-extending lips formed which project from the underside at the perimeter edges. The underside of the pallet has raised ribs, which project from the underside and extend between and up to the downwardly-extending lips. The raised ribs and the downwardly-extending lips allow the pallet to be edge rackable. Legs projecting from the underside of the pallet support the pallet on a surface.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to an apparatus that can be used as a pallet forstoring goods, more specifically, to a plastic mechanical pallet thatcan be used in a manufacturing, distribution or warehouse facility.

2. Description of the Related Art

U.S. Pat. No. 4,562,718 (Dunk) discloses a pallet formed of sheet metalusing a drawing operation. The pallet includes depressions and ribs,which are stamped or drawn into the pallet from the product or loadcarrying side of the pallet.

U.S. Pat. No. 4,674,414 (Nulle et al.) discloses a one-piece pallet witha plurality of legs and channel-like webs. The Legs and the webs areformed from the product side of the pallet and are depressions on theproduct side of the pallet.

U.S. Pat. No. 3,526,195 (Maryonovich) discloses a plastic pallet formedof a single sheet of thermoplastic material. The pallet has ribs andlegs. The legs and the ribs are formed from the product side of thepallet and are depressions on the product side of the pallet. Dependingon a pallet's orientation in relation to another pallet, the pallet iseither nestable or stackable with respect to other pallets.

U.S. Pat. No. 5,791,262 (Knight et al.) discloses a reinforced plasticpallet that is constructed from two separate plastic sheets, which arepressed together at preselected locations.

U.S. Pat. No. 4,809,618 (Bell) discloses a plastic pallet that is formedof injection molded plastic or injection molded plastic foam. The pallethas a flat upper surface and a plurality of supporting legs. The legsare used for providing rigidity and support. The pallet includes liftingribs and strengthening rib on a bottom side of the pallet.

Prior art pallets have the disadvantages that they are not edge rackable(can be supported only by the edges of the pallet when the pallet isloaded) particularly along the longer sides of the pallet. Furthermore,the prior art does not disclose pallets having only seven feet or legs.

SUMMARY OF THE INVENTION

It is accordingly an object of the invention to provide a single-walledhomogeneous plastic pallet which overcomes the above-mentioneddisadvantages of the heretofore-known devices and methods of thisgeneral type and which provides a durable pallet that is easilymanufactured, lightweight, and can be used to hold a variety ofproducts.

With the foregoing and other objects in view there is provided, inaccordance with the invention, a pallet including a single wall ofhomogeneous material defining a substantially flat load-supportingsurface. The substantially flat load-supporting surface has perimeteredges. The single wall has an underside opposite the load-supportingsurface. Raised ribs formed by an increased material thickness of thewall and which project from the underside and extend between and up tothe edges is provided. Deflections in the single wall, which form legsprojecting from the underside, are included.

In accordance with another feature of the invention, there are providedraised lips formed by an increased material thickness of the wall andwhich project from the load-supporting surface at the four edges.

In accordance with a further feature of the invention, the perimeteredges include two opposite substantially parallel longitudinal edges andtwo other substantially parallel opposite edges. The oppositelongitudinal edges are longer than the other two opposite edges.

In accordance with an added feature of the invention, the legs are onlyseven legs, which include four corner legs, a center leg at a center ofthe pallet and two side legs at a middle of the longitudinal sides.

In accordance with an additional feature of the invention, the legs arecored out from the load-supporting surface.

In accordance with yet another feature of the invention, the legs haveholes formed therein for allowing fluid drainage.

In accordance with yet a further feature of the invention, the legs areformed with draft angles a for producing and stacking the pallets.

In accordance with yet an added feature of the invention, the raisedribs include longitudinal raised ribs extending substantially parallelto the longitudinal edges and radial raised ribs radiating from a centerof the pallet.

In accordance with yet an additional feature of the invention, there areprovided downwardly-extending lips formed by an increased materialthickness of the wall and which project from the underside at the fouredges. The material thickness of the downwardly-extending lips is lessthan the material thickness of the raised ribs. The raised ribs have alead in angle β, which blends into the downwardly-extending lips.

In accordance with still another feature of the invention, the raisedribs include longitudinal raised ribs extending substantially parallelto the longitudinal edges and radial raised ribs radiating from a centerof the pallet.

In accordance with still a further feature of the invention, theload-supporting surface has a surface texture.

With the objects of the invention in view, there is also provided, apallet including a single wall of homogeneous material defining asubstantially flat load-supporting surface. The substantially flatload-supporting surface has perimeter edges. The single wall has anunderside opposite the load-supporting surface. Raised lips formed by anincreased material thickness of the wall and which project from theload-supporting surface at the perimeter edges are provided.Downwardly-extending lips formed by an increased material thickness ofthe wall and which project from the underside at the perimeter edges areprovided. Raised ribs formed by an increased material thickness of thewall and which project from the underside and extend between and up tothe downwardly-extending lips are also provided. Deflections in thesingle wall form legs projecting from the underside.

Other features which are considered as characteristic for the inventionare set forth in the appended claims.

Although the invention is illustrated and described herein as embodiedin the plastic pallet, it is nevertheless not intended to be limited tothe details shown, since various modifications and structural changesmay be made therein without departing from the spirit of the inventionand within the scope and range of equivalents of the claims.

The construction and method of operation of the invention, however,together with additional objects and advantages thereof will be bestunderstood from the following description of specific embodiments whenread in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of the pallet according to the invention asseen from the load carrying side;

FIG. 2 is a perspective view of the pallet according to FIG. 1 as seenfrom the underside; and

FIG. 3 is a section through the center of two nested pallets accordingto FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the figures of the drawing in detail and first,particularly, to FIG. 1 thereof, there is seen a single-walled plasticpallet 1 according to the invention. The plastic pallet 1 is produced bya low-pressure structural foam process, which utilizes a chemicalfoaming agent to produce a pallet of homogeneous material. The termhomogeneous material refers to a blend of plastic resin such as HDPE(High Density Polyethylene), filler such as calcium carbonate, and ablowing agent, and a color concentrate. It is also possible to include alow percentage of LDPE (Low Density Polyethylene) as a regrind materialfor lowering material costs. Because the pallet 1 is a single-walledhomogenous part it is completely and easily recyclable.

The pallet 1 includes a substantially planar load-supporting surface 5,which can be provided with a surface texture or surface grain 8 forincreasing the coefficient of friction between the load and the pallet1. The pallet 1 has four perimeter edges, which have raised lips 6,which project in the direction of the load to be supported by thepallet. The raised lips 6 help prevent the load from shifting off of thepallet 1. The four edges of the pallet also have downwardly-extendinglips 11, which extend in a direction away from the load to be supportedby the pallet.

The pallet 1 includes seven legs for supporting the pallet 1 on thefloor or on top of the load of another pallet 1. The legs include fourL-shaped corner legs 4, two side legs 2, located in the center of thelong sides of the pallet 1, and a center leg 3 located in the center ofthe pallet 1. The legs are cored out from the load carrying side of thepallet 1, so as to reduce the weight of the pallet 1 and to reduce thecycle time for producing the pallet 1. The legs are provided withgenerous radii at all their edges, and the legs may have holes 7 intheir bottoms to allow drainage of any liquid that the pallet 1 may beexposed to. The legs can include a draft angle a on their sides to allowthe easy manufacture of the pallet 1 and to allow a plurality of pallets1 to be nested upon one another.

FIG. 2 shows ribs, which are provided only on the underside of thepallet 1. The ribs include longitudinal ribs 10 which are substantiallyparallel to the long side of the pallet 1 and run the entire length ofthe pallet 1 from edge to edge and thus from downwardly-extending lip 11to downwardly-extending lip 11. The ribs also include radial ribs 9,which extend from the center leg 3 of the pallet 1 to thedownwardly-extending lips 11. The radial ribs 9 and the longitudinalribs 10 intersect one another. Both the longitudinal ribs 10 and theradial ribs 9 may be interrupted by any one of the legs, however, theribs continue on the opposite side of the legs to thedownwardly-extending lips 11. At the edges of the pallet 1 each of theribs have a lead in angle β, which blends into the downwardly-extendinglips 11. The angle β allows forks of a forklift to enter a region underthe pallet 1 without damaging the ribs 9, 10.

FIG. 3 shows the pallet in an edge rackable position, where edgerackable is defined as supporting a pallet 1 from its underside by onlysupporting the pallet 1 under two opposing edges of the pallet. Such asupport may be a pair of angle irons.17 mounted on a frame. The pallet 1must have sufficient rigidity to be edge rackable. In the presentinvention the downwardly-extending lips 11 and the ribs 9, 10, whichextend up to the downwardly-extending lips 11, achieve this rigidity.The lead in angle β of the ribs matches the angle of an angle iron onwhich the pallet 1 is edge rackable. Although the ribs 9, 10 have beendisclosed as radial ribs 9 and longitudinal ribs 10, any geometry ofribs can be used as long as sufficient strength is provided for edgeracking of the pallet 1.

FIG. 3 also shows two pallets 1 as they are nested when stacked on topof one another. As can be seen from FIG. 3 the legs fit into therecesses of the legs 2, 3, 4 of the underlying pallet 1. Furthermorewhen nested, the top pallet 1 rests on its ribs 9, 10 on theload-supporting surface 5 of the underlying pallet. The lead in angle βformed on the ribs 9, 10 allows access to separate the pallets 1 whenthey are nested.

1. A pallet, comprising: a single wall of homogeneous material defining a substantially flat load-supporting surface having perimeter edges and an underside opposite said load-supporting surface; raised ribs formed by an increased material thickness of said wall and projecting from said underside and extending between and up to said edges; and deflections in said single wall forming legs projecting from said underside.
 2. The pallet according to claim 1, further comprising raised lips formed by an increased material thickness of said wall and projecting from said load-supporting surface at said four edges.
 3. The pallet according to claim 2, wherein said perimeter edges include two opposite substantially parallel longitudinal edges and two other substantially parallel opposite edges, and said opposite longitudinal edges are longer than said other two opposite edges.
 4. The pallet according to claim 3, wherein said legs are only seven legs including four corner legs, a center leg at a center of the pallet and two side legs at a middle of said longitudinal sides.
 5. The pallet according to claim 4, wherein said legs are cored out from said load-supporting surface.
 6. The pallet according to claim 5, wherein said legs have holes formed therein for allowing fluid drainage.
 7. The pallet according to claim 5 wherein said legs are formed with draft angles a for producing and stacking the pallets.
 8. The pallet according to claim 3, wherein said raised ribs include longitudinal raised ribs extending substantially parallel to said longitudinal edges and radial raised ribs radiating from a center of the pallet.
 9. The pallet according to claim 3, further comprising downwardly-extending lips formed by an increased material thickness of said wall and projecting from said underside at said four edges, said material thickness of said downwardly-extending lips being less than said material thickness of said raised ribs, and said raised ribs having a lead in angle β blending into said downwardly-extending lips.
 10. The pallet according to claim 9, wherein said raised ribs include longitudinal raised ribs extending substantially parallel to said longitudinal edges and radial raised ribs radiating from a center of the pallet.
 11. The pallet according to claim 1, wherein said load-supporting surface has a surface texture.
 12. A pallet, comprising: a single wall of homogeneous material defining a substantially flat load-supporting surface having perimeter edges and an underside opposite said load-supporting surface; raised lips formed by an increased material thickness of said wall and projecting from said load-supporting surface at said perimeter edges; downwardly-extending lips formed by an increased material thickness of said wall and projecting from said underside at said perimeter edges; raised ribs formed by an increased material thickness of said wall and projecting from said underside and extending between and up to said downwardly-extending lips; and deflections in said single wall forming legs projecting from said underside. 